A principle objective of this invention is to provide a non-destructive and efficient means for inspecting contact lens casting cups for edge quality, alignment fit, center thickness, roundness, prism, and a variety of other defects.
There are currently inspection systems capable of imaging the interior of plastic mold assemblies. These systems, however, are limited in scope and typically image on a macro scale (i.e., in inches). Consequently, there is a need for a more precise non-destructive means for inspecting plastic components for parameters such as those described above.
More specifically, there is a need for a means for imaging the interior of casting cups used for molding contact lenses. Previously, inspection methods for such casting cup assemblies related to whether or not the exterior physical dimensions were in accordance with specification. However, exterior dimensions held little statistical significance to the quality of the lens compared with interior dimensions. Lens quality is reflected in part by the presence or absence of edge defects, edge configuration, and center thickness. There is thus a need for an inspection system that can better assess these important attributes.